Professional Web APIs with PHP: eBay, Google, PayPal, Amazon, FedEx, Plus Web Feeds by Paul Reinheimer
Part I - Web Feeds:
Chapter 1 - Introducing Web Services
Chapter 2 - Introducing Web Feeds
Chapter 3 - Consuming Web Feeds
Chapter 4 - Producing Web Feeds
Part II - APIs:
Chapter 5 - Introduction to Web APIs
Chapter 6 - Interacting with the Google API
Chapter 7 - Interacting with the Amazon API
Chapter 8 - Interacting with the FedEx API
Chapter 9 - Interacting with the eBay API
Chapter 10 - Interacting with the PayPal API
Chapter 11 - Other Major APIs
Chapter 12 - Producing Web APIs.Download